Aircraft with a multi-walled fuel tank and a method of manufacturing

ABSTRACT

An aircraft with a multi-walled fuel tank and method of manufacturing is presented. The aircraft includes a blended wing body and a fuel tank attached to the blended wing body configured to store liquified gas fuel. The fuel tank includes an inner wall, outer wall, and interstitial volume in between that is filled with insulation. The interstitial volume includes a reflective film layer and a structural insulation layer.

FIELD OF THE INVENTION

The present invention generally relates to the field of aircraft. Inparticular, the present invention is directed to an aircraft with amulti-walled fuel tank and a method of manufacturing.

BACKGROUND

Hydrogen fuel has characteristics favorable as an aviation fuel.Hydrogen fuel needs to be stored in a liquid form to minimize volume andmaximize efficient flight. Storage of hydrogen fuel within an aircraftis limited by the weight of the storage tank. Existing solutions are notsatisfactory.

SUMMARY OF THE DISCLOSURE

In an aspect an aircraft with at least a multi-walled fuel tank includesa blended wing body, and at least a fuel tank attached to the blendedwing body and configured to store liquified gas fuel, wherein the atleast a fuel tank further comprises: an inner wall, an outer wall, aninterstitial volume between the inner wall and the outer wall comprisingof at least a reflective film layer and at least a structural insulationlayer.

In another aspect a method of manufacturing at least a multi-walled fueltank for an aircraft includes receiving a blended wing body, receivingan inner wall, receiving an outer wall, inserting an interstitial volumecomprising at least a reflective film layer and at least a structuralinsulation layer between the inner wall and the outer wall.

These and other aspects and features of non-limiting embodiments of thepresent invention will become apparent to those skilled in the art uponreview of the following description of specific non-limiting embodimentsof the invention in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, the drawings show aspectsof one or more embodiments of the invention. However, it should beunderstood that the present invention is not limited to the precisearrangements and instrumentalities shown in the drawings, wherein:

FIG. 1 is a schematic of an exemplary blended wing aircraft;

FIG. 2A is an exemplary depiction of a fuel tank;

FIG. 2B is an exemplary depiction of a cross section of a fuel tank;

FIG. 3 is a block diagram of a sensing system;

FIG. 4 is a flow diagram of a method for manufacturing a multi-walledfuel tank; and

FIG. 5 is a block diagram of a computing system that can be used toimplement any one or more of the methodologies disclosed herein and anyone or more portions thereof.

The drawings are not necessarily to scale and may be illustrated byphantom lines, diagrammatic representations and fragmentary views. Incertain instances, details that are not necessary for an understandingof the embodiments or that render other details difficult to perceivemay have been omitted.

DETAILED DESCRIPTION

At a high level, aspects of the present disclosure are directed to anaircraft with a multi-walled fuel tank and a method of manufacturing.Aspects of the present disclosure include a blended wing body. Aspectsof this present disclosure include storing liquified gasfuel in a fueltank. Aspects of the present disclosure further includes a ventconfigured to vent gaseous fuel from the tank and an insulation toreduce thermal transfer to the liquified gas fuel inside. Exemplaryembodiments illustrating aspects of the present disclosure are describedbelow in the context of several specific examples.

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present invention. For purposes of descriptionherein, relating terms, including “upper”, “lower”, “left”, “rear”,“right”, “front”, “vertical”, “horizontal”, and derivatives thereofrelate to embodiments oriented as shown for exemplary purposes in FIG. 1. Furthermore, there is no intention to be bound by any expressed orimplied theory presented in this disclosure.

Referring now to FIG. 1 , an exemplary embodiment of an aircraft 100with multi-walled fuel tanks is illustrated. Aircraft 100 includes ablended wing body 104. For the purposes of this disclosure, a “blendedwing body aircraft” is an aircraft having a blended wing body. As usedin this disclosure, A “blended wing body” (BWB), also known as a“blended body” or a “hybrid wing body” (HWB), is a fixed-wing aircraftbody having no clear or abrupt demarcation between wings and a main bodyof the aircraft along a leading edge of the aircraft. For example, a BWB104 aircraft may have distinct wing and body structures, which aresmoothly blended together with no clear dividing line or boundaryfeature between wing and fuselage. This contrasts with a flying wing,which has no distinct fuselage, and a lifting body, which has nodistinct wings. A BWB 104 design may or may not be tailless. Onepotential advantage of a BWB 104 may be to reduce wetted area and anyaccompanying drag associated with a conventional wing-body junction. Insome cases, a BWB 104 may also have a wide airfoil-shaped body, allowingentire aircraft to generate lift and thereby facilitate reduction insize and/or drag of wings. In some cases, a BWB 104 may be understood asa hybrid shape that resembles a flying wing, but also incorporatesfeatures from conventional aircraft. In some cases, this combination mayoffer several advantages over conventional tube-and-wing airframes. Insome cases, a BWB airframe 104 may help to increase fuel economy andcreate larger payload (cargo or passenger) volumes within the BWB. BWB104 may allow for advantageous interior designs. For instance, cargo canbe loaded and/or passengers can board from the front or rear of theaircraft. A cargo or passenger area may be distributed across arelatively wide (when compared to conventional tube-wing aircraft)fuselage, providing a large usable volume. In some embodiments,passengers seated within an interior of aircraft, real-time video atevery seat can take place of window seats.

With continued reference to FIG. 1 , BWB 104 of aircraft 100 may includea nose portion. A “nose portion,” for the purposes of this disclosure,refers to any portion of aircraft 100 forward of the aircraft's fuselage116. Nose portion may comprise a cockpit (for manned aircraft), canopy,aerodynamic fairings, windshield, and/or any structural elementsrequired to support mechanical loads. Nose portion may also includepilot seats, control interfaces, gages, displays, inceptor sticks,throttle controls, collective pitch controls, and/or communicationequipment, to name a few. Nose portion may comprise a swing noseconfiguration. A swing nose may be characterized by an ability of thenose to move, manually or automatedly, into a differing orientation thanits flight orientation to provide an opening for loading a payload intoaircraft fuselage from the front of the aircraft. Nose portion may beconfigured to open in a plurality of orientations and directions.

With continued reference to FIG. 1 , BWB 104 may include at least astructural component of aircraft 100. Structural components may providephysical stability during an entirety of an aircraft's 100 flightenvelope, while on ground, and during normal operation Structuralcomponents may comprise struts, beams, formers, stringers, longerons,interstitials, ribs, structural skin, doublers, straps, spars, orpanels, to name a few. Structural components may also comprise pillars.In some cases, for the purpose of aircraft cockpits comprisingwindows/windshields, pillars may include vertical or near verticalsupports around a window configured to provide extra stability aroundweak points in a vehicle's structure, such as an opening where a windowis installed. Where multiple pillars are disposed in an aircraft's 100structure, they may be so named A, B, C, and so on named from nose totail. Pillars, like any structural element, may be disposed a distanceaway from each other, along an exterior of aircraft 100 and BWB 104.Depending on manufacturing method of BWB 104, pillars may be integral toframe and skin, comprised entirely of internal framing, oralternatively, may be only integral to structural skin elements.Structural skin will be discussed in greater detail below.

With continued reference to FIG. 1 , BWB 104 may include a plurality ofmaterials, alone or in combination, in its construction. At least a BWB104, in an illustrative embodiment may include a welded steel tube framefurther configured to form a general shape of a nose corresponding to anarrangement of steel tubes. Steel may include any of a plurality ofalloyed metals, including but not limited to, a varying amount ofmanganese, nickel, copper, molybdenum, silicon, and/or aluminum, to namea few. Welded steel tubes may be covered in any of a plurality ofmaterials suitable for aircraft skin. Some of these may include carbonfiber, fiberglass panels, cloth-like materials, aluminum sheeting, orthe like. BWB 104 may comprise aluminum tubing mechanically coupled invarious and orientations. Mechanical fastening of aluminum members(whether pure aluminum or alloys) may comprise temporary or permanentmechanical fasteners appreciable by one of ordinary skill in the artincluding, but not limited to, screws, nuts and bolts, anchors, clips,welding, brazing, crimping, nails, blind rivets, pull-through rivets,pins, dowels, snap-fits, clamps, and the like. BWB 104 may additionallyor alternatively use wood or another suitably strong yet light materialfor an internal structure.

With continued reference to FIG. 1 , aircraft 100 may include monocoqueor semi-monocoque construction. BWB 104 may include carbon fiber. Carbonfiber may include carbon fiber reinforced polymer, carbon fiberreinforced plastic, or carbon fiber reinforced thermoplastic (e.g.,CFRP, CRP, CFRTP, carbon composite, or just carbon, depending onindustry). “Carbon fiber,” as used in this disclosure, is a compositematerial including a polymer reinforced with carbon. In general, carbonfiber composites consist of two parts, a matrix and a reinforcement. Incarbon fiber reinforced plastic, the carbon fiber constitutes thereinforcement, which provides strength. The matrix can include a polymerresin, such as epoxy, to bind reinforcements together. Suchreinforcement achieves an increase in CFRP's strength and rigidity,measured by stress and elastic modulus, respectively. In embodiments,carbon fibers themselves can each comprise a diameter between 5-10micrometers and include a high percentage (i.e. above 85%) of carbonatoms. A person of ordinary skill in the art will appreciate that theadvantages of carbon fibers include high stiffness, high tensilestrength, low weight, high chemical resistance, high temperaturetolerance, and low thermal expansion. According to embodiments, carbonfibers may be combined with other materials to form a composite, whenpermeated with plastic resin and baked, carbon fiber reinforced polymerbecomes extremely rigid. Rigidity may be considered analogous tostiffness which may be measured using Young's Modulus. Rigidity may bedefined as a force necessary to bend and/or flex a material and/orstructure to a given degree. For example, ceramics have high rigidity,which can be visualized by shattering before bending. In embodiments,carbon fibers may additionally, or alternatively, be composited withother materials like graphite to form reinforced carbon-carboncomposites, which include high heat tolerances over 2000° C. A person ofskill in the art will further appreciate that aerospace applications mayrequire high-strength, low-weight, high heat resistance materials in aplurality of roles, such as without limitation fuselages, fairings,control surfaces, and structures, among others.

With continued reference to FIG. 1 , BWB 104 may include at least afuselage. A “fuselage,” for the purposes of this disclosure, refers to amain body of an aircraft 100, or in other words, an entirety of theaircraft 100 except for nose, wings, empennage, nacelles, and controlsurfaces. In some cases, fuselage may contains an aircraft's payload. Atleast a fuselage may comprise structural components that physicallysupport a shape and structure of an aircraft 100. Structural componentsmay take a plurality of forms, alone or in combination with other types.Structural components vary depending on construction type of aircraft100 and specifically, fuselage. A fuselage 112 may include a trussstructure. A truss structure may be used with a lightweight aircraft. Atruss structure may include welded steel tube trusses. A “truss,” asused in this disclosure, is an assembly of beams that create a rigidstructure, for example without limitation including combinations oftriangles to create three-dimensional shapes. A truss structure mayinclude wood construction in place of steel tubes, or a combinationthereof. In some embodiments, structural components can comprise steeltubes and/or wood beams. An aircraft skin may be layered over a bodyshape constructed by trusses. Aircraft skin may comprise a plurality ofmaterials such as plywood sheets, aluminum, fiberglass, and/or carbonfiber.

With continued reference to FIG. 1 , in embodiments, at least a fuselagemay comprise geodesic construction. Geodesic structural elements mayinclude stringers wound about formers (which may be alternatively calledstation frames) in opposing spiral directions. A “stringer,” for thepurposes of this disclosure is a general structural element thatincludes a long, thin, and rigid strip of metal or wood that ismechanically coupled to and spans the distance from, station frame tostation frame to create an internal skeleton on which to mechanicallycouple aircraft skin. A former (or station frame) can include a rigidstructural element that is disposed along a length of an interior of afuselage orthogonal to a longitudinal (nose to tail) axis of aircraft100. In some cases, a former forms a general shape of at least afuselage. A former may include differing cross-sectional shapes atdiffering locations along a fuselage, as the former is a structuralcomponent that informs an overall shape of the fuselage. In embodiments,aircraft skin can be anchored to formers and strings such that an outermold line of volume encapsulated by the formers and stringers comprisesa same shape as aircraft 100 when installed. In other words, former(s)may form a fuselage's ribs, and stringers may form interstitials betweenthe ribs. A spiral orientation of stringers about formers may provideuniform robustness at any point on an aircraft fuselage such that if aportion sustains damage, another portion may remain largely unaffected.Aircraft skin may be mechanically coupled to underlying stringers andformers and may interact with a fluid, such as air, to generate lift andperform maneuvers.

With continued reference to FIG. 1 , according to some embodiments, afuselage can comprise monocoque construction. Monocoque construction caninclude a primary structure that forms a shell (or skin in an aircraft'scase) and supports physical loads. Monocoque fuselages are fuselages inwhich the aircraft skin or shell may also include a primary structure.In monocoque construction aircraft skin would support tensile andcompressive loads within itself and true monocoque aircraft can befurther characterized by an absence of internal structural elements.Aircraft skin in this construction method may be rigid and can sustainits shape with substantially no structural assistance form underlyingskeleton-like elements. Monocoque fuselage may include aircraft skinmade from plywood layered in varying grain directions, epoxy-impregnatedfiberglass, carbon fiber, or any combination thereof.

With continued reference to FIG. 1 , according to some embodiments, afuselage may include a semi-monocoque construction. Semi-monocoqueconstruction, as used in this disclosure, is used interchangeably withpartially monocoque construction, discussed above. In semi-monocoqueconstruction, a fuselage may derive some structural support fromstressed aircraft skin and some structural support from underlying framestructure made of structural components. Formers or station frames canbe seen running transverse to a long axis of fuselage with circularcutouts which are may be used in real-world manufacturing for weightsavings and for routing of electrical harnesses and other modernon-board systems. In a semi-monocoque construction, stringers may bethin, long strips of material that run parallel to a fuselage's longaxis. Stringers can be mechanically coupled to formers permanently, suchas with rivets. Aircraft skin can be mechanically coupled to stringersand formers permanently, such as by rivets as well. A person of ordinaryskill in the art will appreciate that there are numerous methods formechanical fastening of the aforementioned components like screws,nails, dowels, pins, anchors, adhesives like glue or epoxy, or bolts andnuts, to name a few. According to some embodiments, a subset ofsemi-monocoque construction may be unibody construction. Unibody, whichis short for “unitized body” or alternatively “unitary construction”,vehicles are characterized by a construction in which body, floor plan,and chassis form a single structure, for example an automobile. In theaircraft world, a unibody may include internal structural elements, likeformers and stringers, constructed in one piece, integral to an aircraftskin. In some cases, stringers and formers may account for a bulk of anyaircraft structure (excluding monocoque construction). Stringers andformers can be arranged in a plurality of orientations depending onaircraft operation and materials. Stringers may be arranged to carryaxial (tensile or compressive), shear, bending or torsion forcesthroughout their overall structure. Due to their coupling to aircraftskin, aerodynamic forces exerted on aircraft skin may be transferred tostringers. Location of said stringers greatly informs type of forces andloads applied to each and every stringer, all of which may be accountedfor through design processes including, material selection,cross-sectional area, and mechanical coupling methods of each member.Similar methods may be performed for former assessment and design. Ingeneral, formers may be significantly larger in cross-sectional area andthickness, depending on location, than stringers. Both stringers andformers may comprise aluminum, aluminum alloys, graphite epoxycomposite, steel alloys, titanium, or an undisclosed material alone orin combination.

With continued reference to FIG. 1 , in some cases, a primary purposefor a substructure of a semi-monocoque structure is to stabilize a skin.Typically, aircraft structure is required to have a very light weightand as a result, in some cases, aircraft skin may be very thin. In somecases, unless supported, this thin skin structure may tend to buckleand/or cripple under compressive and/or shear loads. In some cases,underlying structure may be primarily configured to stabilize skins. Forexample, in an exemplary conventional airliner, wing structure is anairfoil-shaped box with truncated nose and aft triangle; withoutstabilizing substructure, in some cases, this box would buckle upperskin of the wing and the upper skin would also collapse into the lowerskin under bending loads. In some cases, deformations are prevented withribs that support stringers which stabilize the skin. Fuselages aresimilar with bulkheads or frames, and stringers.

With continued reference to FIG. 1 , in some embodiments, another commonstructural form is sandwich structure. As used in this disclosure,“sandwich structure” includes a skin structure having an inner and outerskin separated and stabilized by a core material. In some cases,sandwich structure may additionally include some number of ribs orframes. In some cases, sandwich structure may include metal, polymer,and/or composite. In some cases, core material may include honeycomb,foam plastic, and/or end-grain balsa wood. In some cases, sandwichstructure can be popular on composite light airplanes, such as glidersand powered light planes. In some cases, sandwich structure may not usestringers, and sandwich structure may allow number of ribs or frames tobe reduced, for instance in comparison with a semi-monocoque structure.In some cases, sandwich structure may be suitable for smaller, possiblyunmanned, unpressurized blended wing body aircraft.

With continued reference to FIG. 1 , stressed skin, when used insemi-monocoque construction, may bear partial, yet significant, load. Inother words, an internal structure, whether it be a frame of weldedtubes, formers and stringers, or some combination, is not sufficientlystrong enough by design to bear all loads. The concept of stressed skinis applied in monocoque and semi-monocoque construction methods of atleast a fuselage and/or BWB 104. In some cases, monocoque may beconsidered to include substantially only structural skin, and in thatsense, aircraft skin undergoes stress by applied aerodynamic fluidsimparted by fluid. Stress as used in continuum mechanics can bedescribed in pound-force per square inch (lbf/in²) or Pascals (Pa). Insemi-monocoque construction stressed skin bears part of aerodynamicloads and additionally imparts force on an underlying structure ofstringers and formers.

With continued reference to FIG. 1 , a fuselage may include an interiorcavity. An interior cavity may include a volumetric space configurableto house passenger seats and/or cargo. An interior cavity may beconfigured to include receptacles for fuel tanks, batteries, fuel cells,or other energy sources as described herein. In some cases, a post maybe supporting a floor (i.e., deck), or in other words a surface on whicha passenger, operator, passenger, payload, or other object would rest ondue to gravity when within an aircraft 100 is in its level flightorientation or sitting on ground. A post may act similarly to stringerin that it is configured to support axial loads in compression due to aload being applied parallel to its axis due to, for example, a heavyobject being placed on a floor of aircraft 100. A beam may be disposedin or on any portion a fuselage that requires additional bracing,specifically when disposed transverse to another structural element,like a post, that would benefit from support in that direction, opposingapplied force. A beam may be disposed in a plurality of locations andorientations within a fuselage as necessitated by operational andconstructional requirements.

With continued reference to FIG. 1 , aircraft 100 may include at least aflight component 108. A flight component 108 may be consistent with anydescription of a flight component described in this disclosure, such aswithout limitation propulsors, control surfaces, rotors, paddle wheels,engines, propellers, wings, winglets, or the like. For the purposes ofthis disclosure, at least a “flight component” is at least one elementof an aircraft 100 configured to manipulate a fluid medium such as airto propel, control, or maneuver an aircraft. In nonlimiting examples, atleast a flight component may include a rotor mechanically connected to arotor shaft of an electric motor further mechanically affixed to atleast a portion of aircraft 100. In some embodiments, at least a flightcomponent 108 may include a propulsor, for example a rotor attached toan electric motor configured to produce shaft torque and in turn, createthrust. As used in this disclosure, an “electric motor” is an electricalmachine that converts electric energy into mechanical work.

With continued reference to FIG. 1 , for the purposes of thisdisclosure, “torque”, is a twisting force that tends to cause rotation.Torque may be considered an effort and a rotational analogue to linearforce. A magnitude of torque of a rigid body may depend on threequantities: a force applied, a lever arm vector connecting a point aboutwhich the torque is being measured to a point of force application, andan angle between the force and the lever arm vector. A force appliedperpendicularly to a lever multiplied by its distance from the lever'sfulcrum (the length of the lever arm) is its torque. A force of threenewtons applied two meters from the fulcrum, for example, exerts thesame torque as a force of one newton applied six meters from thefulcrum. In some cases, direction of a torque can be determined by usinga right-hand grip rule which states: if fingers of right hand are curledfrom a direction of lever arm to direction of force, then thumb pointsin a direction of the torque. One of ordinary skill in the art wouldappreciate that torque may be represented as a vector, consistent withthis disclosure, and therefore may include a magnitude and a direction.“Torque” and “moment” are used interchangeably within this disclosure.Any torque command or signal within this disclosure may include at leastthe steady state torque to achieve the torque output to at least apropulsor.

With continued reference to FIG. 1 , at least a flight component may beone or more devices configured to affect aircraft's 100 attitude.“Attitude”, for the purposes of this disclosure, is the relativeorientation of a body, in this case aircraft 100, as compared to earth'ssurface or any other reference point and/or coordinate system. In somecases, attitude may be displayed to pilots, personnel, remote users, orone or more computing devices in an attitude indicator, such as withoutlimitation a visual representation of a horizon and its relativeorientation to aircraft 100. A plurality of attitude datums may indicateone or more measurements relative to an aircraft's pitch, roll, yaw, orthrottle compared to a relative starting point. One or more sensors maymeasure or detect an aircraft's 100 attitude and establish one or moreattitude datums. An “attitude datum”, for the purposes of thisdisclosure, refers to at least an element of data identifying anattitude of an aircraft 100.

With continued reference to FIG. 1 , in some cases, aircraft 100 mayinclude one or more of an angle of attack sensor and a yaw sensor. Insome embodiments, one or more of an angle of attack sensor and a yawsensor may include a vane (e.g., wind vane). In some cases, vane mayinclude a protrusion on a pivot with an aft tail. The protrusion may beconfigured to rotate about pivot to maintain zero tail angle of attack.In some cases, pivot may turn an electronic device that reports one ormore of angle of attack and/or yaw, depending on, for example,orientation of the pivot and tail. Alternatively or additionally, insome cases, one or more of angle of attack sensor and/or yaw sensor mayinclude a plurality of pressure ports located in selected locations,with pressure sensors located at each pressure port. In some cases,differential pressure between pressure ports can be used to estimateangle of attack and/or yaw.

With continued reference to FIG. 1 , in some cases, aircraft 100 mayinclude at least a pilot control. As used in this disclosure, a “pilotcontrol,” is an interface device that allows an operator, human ormachine, to control a flight component of an aircraft. Pilot control maybe communicatively connected to any other component presented inaircraft 100, the communicative connection may include redundantconnections configured to safeguard against single-point failure. Insome cases, a plurality of attitude datums may indicate a pilot'sinstruction to change heading and/or trim of an aircraft 100. Pilotinput may indicate a pilot's instruction to change an aircraft's pitch,roll, yaw, throttle, and/or any combination thereof. Aircraft trajectorymay be manipulated by one or more control surfaces and propulsorsworking alone or in tandem consistent with the entirety of thisdisclosure. “Pitch”, for the purposes of this disclosure refers to anaircraft's angle of attack, that is a difference between a planeincluding at least a portion of both wings of the aircraft running noseto tail and a horizontal flight trajectory. For example, an aircraft maypitch “up” when its nose is angled upward compared to horizontal flight,as in a climb maneuver. In another example, an aircraft may pitch“down”, when its nose is angled downward compared to horizontal flight,like in a dive maneuver. In some cases, angle of attack may not be usedas an input, for instance pilot input, to any system disclosed herein;in such circumstances proxies may be used such as pilot controls, remotecontrols, or sensor levels, such as true airspeed sensors, pitot tubes,pneumatic/hydraulic sensors, and the like. “Roll” for the purposes ofthis disclosure, refers to an aircraft's position about its longitudinalaxis, that is to say that when an aircraft rotates about its axis fromits tail to its nose, and one side rolls upward, as in a bankingmaneuver. “Yaw”, for the purposes of this disclosure, refers to anaircraft's turn angle, when an aircraft rotates about an imaginaryvertical axis intersecting center of earth and aircraft 100. “Throttle”,for the purposes of this disclosure, refers to an aircraft outputting anamount of thrust from a propulsor. In context of a pilot input, throttlemay refer to a pilot's input to increase or decrease thrust produced byat least a propulsor. Flight components 108 may receive and/or transmitsignals, for example an aircraft command signal. Aircraft command signalmay include any signal described in this disclosure, such as withoutlimitation electrical signal, optical signal, pneumatic signal,hydraulic signal, and/or mechanical signal. In some cases, an aircraftcommand may be a function of a signal from a pilot control. In somecases, an aircraft command may include or be determined as a function ofa pilot command. For example, aircraft commands may be determined as afunction of a mechanical movement of a throttle. Signals may includeanalog signals, digital signals, periodic or aperiodic signal, stepsignals, unit impulse signal, unit ramp signal, unit parabolic signal,signum function, exponential signal, rectangular signal, triangularsignal, sinusoidal signal, sinc function, or pulse width modulatedsignal. Pilot control may include circuitry, computing devices,electronic components or a combination thereof that translates pilotinput into a signal configured to be transmitted to another electroniccomponent. In some cases, a plurality of attitude commands maydetermined as a function of an input to a pilot control. A plurality ofattitude commands may include a total attitude command datum, such as acombination of attitude adjustments represented by one or a certainnumber of combinatorial datums. A plurality of attitude commands mayinclude individual attitude datums representing total or relative changein attitude measurements relative to pitch, roll, yaw, and throttle.

With continued reference to FIG. 1 , in some embodiments, pilot controlmay include at least a sensor. As used in this disclosure, a “sensor” isa device that detects a phenomenon. In some cases, a sensor may detect aphenomenon and transmit a signal that is representative of thephenomenon. At least a sensor may include, torque sensor, gyroscope,accelerometer, magnetometer, inertial measurement unit (IMU), pressuresensor, force sensor, proximity sensor, displacement sensor, vibrationsensor, among others. At least a sensor may include a sensor suite whichmay include a plurality of sensors that may detect similar or uniquephenomena. For example, in a non-limiting embodiment, sensor suite mayinclude a plurality of accelerometers, a mixture of accelerometers andgyroscopes, or a mixture of an accelerometer, gyroscope, and torquesensor. For the purposes of the disclosure, a “torque datum” is one ormore elements of data representing one or more parameters detailingpower output by one or more propulsors, flight components, or otherelements of an electric aircraft. A torque datum may indicate the torqueoutput of at least a flight component 108. At least a flight component108 may include any propulsor as described herein. In embodiment, atleast a flight component 108 may include an electric motor, a propeller,a jet engine, a paddle wheel, a rotor, turbine, or any other mechanismconfigured to manipulate a fluid medium to propel an aircraft asdescribed herein. an embodiment of at least a sensor may include or beincluded in, a sensor suite. The herein disclosed system and method maycomprise a plurality of sensors in the form of individual sensors or asensor suite working in tandem or individually. A sensor suite mayinclude a plurality of independent sensors, as described herein, whereany number of the described sensors may be used to detect any number ofphysical or electrical quantities associated with an aircraft powersystem or an electrical energy storage system. Independent sensors mayinclude separate sensors measuring physical or electrical quantitiesthat may be powered by and/or in communication with circuitsindependently, where each may signal sensor output to a control circuitsuch as a user graphical interface. In a non-limiting example, there maybe four independent sensors housed in and/or on battery pack measuringtemperature, electrical characteristic such as voltage, amperage,resistance, or impedance, or any other parameters and/or quantities asdescribed in this disclosure. In an embodiment, use of a plurality ofindependent sensors may result in redundancy configured to employ morethan one sensor that measures the same phenomenon, those sensors beingof the same type, a combination of, or another type of sensor notdisclosed, so that in the event one sensor fails, the ability of abattery management system and/or user to detect phenomenon is maintainedand in a non-limiting example, a user alter aircraft usage pursuant tosensor readings.

With continued reference to FIG. 1 , at least a sensor may include amoisture sensor. “Moisture”, as used in this disclosure, is the presenceof water, this may include vaporized water in air, condensation on thesurfaces of objects, or concentrations of liquid water. Moisture mayinclude humidity. “Humidity”, as used in this disclosure, is theproperty of a gaseous medium (almost always air) to hold water in theform of vapor. An amount of water vapor contained within a parcel of aircan vary significantly. Water vapor is generally invisible to the humaneye and may be damaging to electrical components. There are threeprimary measurements of humidity, absolute, relative, specific humidity.“Absolute humidity,” for the purposes of this disclosure, describes thewater content of air and is expressed in either grams per cubic metersor grams per kilogram. “Relative humidity”, for the purposes of thisdisclosure, is expressed as a percentage, indicating a present stat ofabsolute humidity relative to a maximum humidity given the sametemperature. “Specific humidity”, for the purposes of this disclosure,is the ratio of water vapor mass to total moist air parcel mass, whereparcel is a given portion of a gaseous medium. A moisture sensor may bepsychrometer. A moisture sensor may be a hygrometer. A moisture sensormay be configured to act as or include a humidistat. A “humidistat”, forthe purposes of this disclosure, is a humidity-triggered switch, oftenused to control another electronic device. A moisture sensor may usecapacitance to measure relative humidity and include in itself, or as anexternal component, include a device to convert relative humiditymeasurements to absolute humidity measurements. “Capacitance”, for thepurposes of this disclosure, is the ability of a system to store anelectric charge, in this case the system is a parcel of air which may benear, adjacent to, or above a battery cell.

With continued reference to FIG. 1 , at least a sensor may include a gassensor. Gas sensor may detect gas that may be emitted through the energysource such as a fuel tank and/or battery. Gaseous discharge may includeoxygen, hydrogen, carbon dioxide, methane, carbon monoxide, acombination thereof, or another undisclosed gas, alone or incombination. Further the sensor configured to detect vent gas from fueltanks and/or other energy sources may comprise a gas detector. For thepurposes of this disclosure, a “gas detector” is a device used to detecta gas is present in an area. Gas detectors, and more specifically, thegas sensor that may be used in sensing system, as discussed in FIG. 2 ,may be configured to detect combustible, flammable, toxic, oxygendepleted, a combination thereof, or another type of gas alone or incombination. The gas sensor that may include a combustible gas,photoionization detectors, electrochemical gas sensors, ultrasonicsensors, metal-oxide-semiconductor (MOS) sensors, infrared imagingsensors, a combination thereof, or another undisclosed type of gassensor alone or in combination. Sensor may also be configured to detectnon-gaseous byproducts from battery cell failure and/or fuel tanksincluding, in non-limiting examples, liquid chemical leaks includingaqueous alkaline solution, ionomer, molten phosphoric acid, liquidelectrolytes with redox shuttle and ionomer, and salt water, amongothers.

With continued reference to FIG. 1 , at least a sensor may includeelectrical sensors. An electrical sensor may be configured to measurevoltage across a component, electrical current through a component, andresistance of a component. Electrical sensors may include separatesensors to measure each of the previously disclosed electricalcharacteristics such as voltmeter, ammeter, and ohmmeter, respectively.One or more sensors may be communicatively coupled to at least a pilotcontrol, the manipulation of which, may constitute at least an aircraftcommand. Signals may include electrical, electromagnetic, visual, audio,radio waves, or another undisclosed signal type alone or in combination.At least a sensor communicatively connected to at least a pilot controlmay include a sensor disposed on, near, around or within at least pilotcontrol. At least a sensor may include a motion sensor. “Motion sensor”,for the purposes of this disclosure refers to a device or componentconfigured to detect physical movement of an object or grouping ofobjects. One of ordinary skill in the art would appreciate, afterreviewing the entirety of this disclosure, that motion may include aplurality of types including but not limited to: spinning, rotating,oscillating, gyrating, jumping, sliding, reciprocating, or the like. Atleast a sensor may include, torque sensor, gyroscope, accelerometer,torque sensor, magnetometer, inertial measurement unit (IMU), pressuresensor, force sensor, proximity sensor, displacement sensor, vibrationsensor, among others. At least a sensor may include a sensor suite whichmay include a plurality of sensors that may detect similar or uniquephenomena. For example, in a non-limiting embodiment, sensor suite mayinclude a plurality of accelerometers, a mixture of accelerometers andgyroscopes, or a mixture of an accelerometer, gyroscope, and torquesensor. The herein disclosed system and method may comprise a pluralityof sensors in the form of individual sensors or a sensor suite workingin tandem or individually. A sensor suite may include a plurality ofindependent sensors, as described herein, where any number of thedescribed sensors may be used to detect any number of physical orelectrical quantities associated with an aircraft power system or anelectrical energy storage system. Independent sensors may includeseparate sensors measuring physical or electrical quantities that may bepowered by and/or in communication with circuits independently, whereeach may signal sensor output to a control circuit such as a usergraphical interface. In an embodiment, use of a plurality of independentsensors may result in redundancy configured to employ more than onesensor that measures the same phenomenon, those sensors being of thesame type, a combination of, or another type of sensor not disclosed, sothat in the event one sensor fails, the ability to detect phenomenon ismaintained and in a non-limiting example, a user alter aircraft usagepursuant to sensor readings.

With continued reference to FIG. 1 , at least a flight component 108 mayinclude wings, empennages, nacelles, control surfaces, fuselages, andlanding gear, among others, to name a few. In embodiments, an empennagemay be disposed at the aftmost point of an aircraft body 104. Empennagemay comprise a tail of aircraft 100, further comprising rudders,vertical stabilizers, horizontal stabilizers, stabilators, elevators,trim tabs, among others. At least a portion of empennage may bemanipulated directly or indirectly by pilot commands to impart controlforces on a fluid in which the aircraft 100 is flying. Manipulation ofthese empennage control surfaces may, in part, change an aircraft'sheading in pitch, roll, and yaw. Wings comprise may include structureswhich include airfoils configured to create a pressure differentialresulting in lift. Wings are generally disposed on a left and right sideof aircraft 100 symmetrically, at a point between nose and empennage.Wings may comprise a plurality of geometries in planform view, sweptswing, tapered, variable wing, triangular, oblong, elliptical, square,among others. Wings may be blended into the body of the aircraft such asin a BWB 104 aircraft 100 where no strong delineation of body and wingexists. A wing's cross section geometry may comprise an airfoil. An“airfoil” as used in this disclosure, is a shape specifically designedsuch that a fluid flowing on opposing sides of it exert differing levelsof pressure against the airfoil. In embodiments, a bottom surface of anaircraft can be configured to generate a greater pressure than does atop surface, resulting in lift. A wing may comprise differing and/orsimilar cross-sectional geometries over its cord length, e.g. lengthfrom wing tip to where wing meets the aircraft's body. One or more wingsmay be symmetrical about an aircraft's longitudinal plane, whichcomprises a longitudinal or roll axis reaching down a center of theaircraft through the nose and empennage, and the aircraft's yaw axis. Insome cases, wings may comprise controls surfaces configured to becommanded by a pilot and/or autopilot to change a wing's geometry andtherefore its interaction with a fluid medium. Flight component 108 mayinclude control surfaces. Control surfaces may include withoutlimitation flaps, ailerons, tabs, spoilers, and slats, among others. Insome cases, control surfaces may be disposed on wings in a plurality oflocations and arrangements. In some cases, control surfaces may bedisposed at leading and/or trailing edges of wings, and may beconfigured to deflect up, down, forward, aft, or any combinationthereof.

In some cases, flight component 108 may include a winglet. For thepurposes of this disclosure, a “winglet” is a flight componentconfigured to manipulate a fluid medium and is mechanically attached toa wing or aircraft and may alternatively called a “wingtip device.”Wingtip devices may be used to improve efficiency of fixed-wing aircraftby reducing drag. Although there are several types of wingtip deviceswhich function in different manners, their intended effect may be toreduce an aircraft's drag by partial recovery of tip vortex energy.Wingtip devices can also improve aircraft handling characteristics andenhance safety for aircraft 100. Such devices increase an effectiveaspect ratio of a wing without greatly increasing wingspan. Extendingwingspan may lower lift-induced drag, but would increase parasitic dragand would require boosting the strength and weight of the wing. As aresult according to some aeronautic design equations, a maximum wingspanmade be determined above which no net benefit exits from furtherincreased span. There may also be operational considerations that limitthe allowable wingspan (e.g., available width at airport gates).

Wingtip devices, in some cases, may increase lift generated at wingtip(by smoothing airflow across an upper wing near the wingtip) and reducelift-induced drag caused by wingtip vortices, thereby improving alift-to-drag ratio. This increases fuel efficiency in powered aircraftand increases cross-country speed in gliders, in both cases increasingrange. U.S. Air Force studies indicate that a given improvement in fuelefficiency correlates directly and causally with increase in anaircraft's lift-to-drag ratio. The term “winglet” has previously beenused to describe an additional lifting surface on an aircraft, like ashort section between wheels on fixed undercarriage. An upward angle(i.e., cant) of a winglet, its inward or outward angle (i.e, toe), aswell as its size and shape are selectable design parameters which may bechosen for correct performance in a given application. A wingtip vortex,which rotates around from below a wing, strikes a cambered surface of awinglet, generating a force that angles inward and slightly forward. Awinglet's relation to a wingtip vortex may be considered analogous tosailboat sails when sailing to windward (i.e., close-hauled). Similar tothe close-hauled sailboat's sails, winglets may convert some of whatwould otherwise-be wasted energy in a wingtip vortex to an apparentthrust. This small contribution can be worthwhile over the aircraft'slifetime. Another potential benefit of winglets is that they may reducean intensity of wake vortices. Wake vortices may trail behind anaircraft 100 and pose a hazard to other aircraft. Minimum spacingrequirements between aircraft at airports are largely dictated byhazards, like those from wake vortices. Aircraft are classified byweight (e.g., “Light,” “Heavy,” and the like) often base upon vortexstrength, which grows with an aircraft's lift coefficient. Thus,associated turbulence is greatest at low speed and high weight, whichmay be produced at high angle of attack near airports. Winglets andwingtip fences may also increase efficiency by reducing vortexinterference with laminar airflow near wingtips, by moving a confluenceof low-pressure air (over wing) and high-pressure air (under wing) awayfrom a surface of the wing. Wingtip vortices create turbulence, whichmay originate at a leading edge of a wingtip and propagate backwards andinboard. This turbulence may delaminate airflow over a small triangularsection of an outboard wing, thereby frustrating lift in that area. Afence/winglet drives an area where a vortex forms upward away from awing surface, as the resulting vortex is repositioned to a top tip ofthe winglet.

With continued reference to FIG. 1 , aircraft 100 may include an energysource. Energy source may include any device providing energy to atleast a flight component 108, for example at least a propulsors. Energysource may include, without limitation, a generator, a photovoltaicdevice, a fuel cell such as a hydrogen fuel cell, direct methanol fuelcell, and/or solid oxide fuel cell, or an electric energy storagedevice; electric energy storage device may include without limitation abattery, a capacitor, and/or inductor. The energy source and/or energystorage device may include at least a battery, battery cell, and/or aplurality of battery cells connected in series, in parallel, or in acombination of series and parallel connections such as seriesconnections into modules that are connected in parallel with other likemodules. Battery and/or battery cell may include, without limitation, Liion batteries which may include NCA, NMC, Lithium iron phosphate(LiFePO4) and Lithium Manganese Oxide (LMO) batteries, which may bemixed with another cathode chemistry to provide more specific power ifthe application requires Li metal batteries, which have a lithium metalanode that provides high power on demand, Li ion batteries that have asilicon or titanite anode. In embodiments, the energy source may be usedto provide electrical power to an electric or hybrid propulsor duringmoments requiring high rates of power output, including withoutlimitation takeoff, landing, thermal de-icing and situations requiringgreater power output for reasons of stability, such as high turbulencesituations. In some cases, battery may include, without limitation abattery using nickel based chemistries such as nickel cadmium or nickelmetal hydride, a battery using lithium ion battery chemistries such as anickel cobalt aluminum (NCA), nickel manganese cobalt (NMC), lithiumiron phosphate (LiFePO4), lithium cobalt oxide (LCO), and/or lithiummanganese oxide (LMO), a battery using lithium polymer technology,lead-based batteries such as without limitation lead acid batteries,metal-air batteries, or any other suitable battery. A person of ordinaryskill in the art, upon reviewing the entirety of this disclosure, willbe aware of various devices of components that may be used as an energysource.

With continued reference to FIG. 1 , in further nonlimiting embodiments,an energy source may include a fuel store. As used in this disclosure, a“fuel store” is an aircraft component configured to store a fuel. Insome cases, a fuel store may include a fuel tank. Fuel may include aliquid fuel, a gaseous fluid, a solid fuel, and fluid fuel, a plasmafuel, and the like. As used in this disclosure, a “fuel” may include anysubstance that stores energy. Exemplary non-limiting fuels includehydrocarbon fuels, petroleum-based fuels, synthetic fuels, chemicalfuels, Jet fuels (e.g., Jet-A fuel, Jet-B fuel, and the like),kerosene-based fuel, gasoline-based fuel, an electrochemical-based fuel(e.g., lithium-ion battery), a hydrogen-based fuel, natural gas-basedfuel, and the like. As described in greater detail below fuel store maybe located substantially within blended wing body 104 of aircraft 100,for example without limitation within a wing portion 112 of blended wingbody 108. Aviation fuels may include petroleum-based fuels, or petroleumand synthetic fuel blends, used to power aircraft 100. In some cases,aviation fuels may have more stringent requirements than fuels used forground use, such as heating and road transport. Aviation fuels maycontain additives to enhance or maintain properties important to fuelperformance or handling. Fuel may be kerosene-based (JP-8 and Jet A-1),for example for gas turbine-powered aircraft. Piston-engine aircraft mayuse gasoline-based fuels and/or kerosene-based fuels (for example forDiesel engines). In some cases, specific energy may be considered animportant criterion in selecting fuel for an aircraft 100. Liquid fuelmay include Jet-A. Presently Jet-A powers modern commercial airlinersand is a mix of extremely refined kerosene and burns at temperatures ator above 49° C. (120° F.). Kerosene-based fuel has a much higher flashpoint than gasoline-based fuel, meaning that it requires significantlyhigher temperature to ignite.

With continued reference to FIG. 1 , modular aircraft 100 may include anenergy source which may include a fuel cell. As used in this disclosure,a “fuel cell” is an electrochemical device that combines a fuel and anoxidizing agent to create electricity. In some cases, fuel cells aredifferent from most batteries in requiring a continuous source of fueland oxygen (usually from air) to sustain the chemical reaction, whereasin a battery the chemical energy comes from metals and their ions oroxides that are commonly already present in the battery, except in flowbatteries. Fuel cells can produce electricity continuously for as longas fuel and oxygen are supplied.

With continued reference to FIG. 1 , in some embodiments, fuel cells mayconsist of different types. Commonly a fuel cell consists of an anode, acathode, and an electrolyte that allows ions, often positively chargedhydrogen ions (protons), to move between two sides of the fuel cell. Atanode, a catalyst causes fuel to undergo oxidation reactions thatgenerate ions (often positively charged hydrogen ions) and electrons.Ions move from anode to cathode through electrolyte. Concurrently,electrons may flow from anode to cathode through an external circuit,producing direct current electricity. At cathode, another catalystcauses ions, electrons, and oxygen to react, forming water and possiblyother products. Fuel cells may be classified by type of electrolyte usedand by difference in startup time ranging from 1 second forproton-exchange membrane fuel cells (PEM fuel cells, or PEMFC) to 10minutes for solid oxide fuel cells (SOFC). In some cases, energy sourcemay include a related technology, such as flow batteries. Within a flowbattery fuel can be regenerated by recharging. Individual fuel cellsproduce relatively small electrical potentials, about 0.7 volts.Therefore, in some cases, fuel cells may be “stacked”, or placed inseries, to create sufficient voltage to meet an application'srequirements. In addition to electricity, fuel cells may produce water,heat and, depending on the fuel source, very small amounts of nitrogendioxide and other emissions. Energy efficiency of a fuel cell isgenerally between 40 and 90%.

Fuel cell may include an electrolyte. In some cases, electrolyte maydefine a type of fuel cell. Electrolyte may include any number ofsubstances like potassium hydroxide, salt carbonates, and phosphoricacid. Commonly a fuel cell is fueled by hydrogen. Fuel cell may featurean anode catalyst, like fine platinum powder, which breaks down fuelinto electrons and ions. Fuel cell may feature a cathode catalyst, oftennickel, which converts ions into waste chemicals, with water being themost common type of waste. A fuel cell may include gas diffusion layersthat are designed to resist oxidization.

With continued reference to FIG. 1 , aircraft 100 may include an energysource which may include a cell such as a battery cell, or a pluralityof battery cells making a battery module. An energy source may be aplurality of energy sources. The module may include batteries connectedin parallel or in series or a plurality of modules connected either inseries or in parallel designed to deliver both the power and energyrequirements of the application. Connecting batteries in series mayincrease the voltage of an energy source which may provide more power ondemand. High voltage batteries may require cell matching when high peakload is needed. As more cells are connected in strings, there may existthe possibility of one cell failing which may increase resistance in themodule and reduce the overall power output as the voltage of the modulemay decrease as a result of that failing cell. Connecting batteries inparallel may increase total current capacity by decreasing totalresistance, and it also may increase overall amp-hour capacity. Theoverall energy and power outputs of an energy source may be based on theindividual battery cell performance or an extrapolation based on themeasurement of at least an electrical parameter. In an embodiment wherean energy source includes a plurality of battery cells, the overallpower output capacity may be dependent on the electrical parameters ofeach individual cell. If one cell experiences high self-discharge duringdemand, power drawn from an energy source may be decreased to avoiddamage to the weakest cell. An energy source may further include,without limitation, wiring, conduit, housing, cooling system and batterymanagement system. Persons skilled in the art will be aware, afterreviewing the entirety of this disclosure, of many different componentsof an energy source.

With continued reference to FIG. 1 , aircraft 100 may include multipleflight component 108 sub-systems, each of which may have a separateenergy source. For instance, and without limitation, one or more flightcomponents 108 may have a dedicated energy source. Alternatively, oradditionally, a plurality of energy sources may each provide power totwo or more flight components 108, such as, without limitation, a “fore”energy source providing power to flight components located toward afront of an aircraft 100, while an “aft” energy source provides power toflight components located toward a rear of the aircraft 100. As afurther non-limiting example, a flight component of group of flightcomponents may be powered by a plurality of energy sources. For example,and without limitation, two or more energy sources may power one or moreflight components; two energy sources may include, without limitation,at least a first energy source having high specific energy density andat least a second energy source having high specific power density,which may be selectively deployed as required for higher-power andlower-power needs. Alternatively, or additionally, a plurality of energysources may be placed in parallel to provide power to the same singlepropulsor or plurality of propulsors 108. Alternatively, oradditionally, two or more separate propulsion subsystems may be joinedusing intertie switches (not shown) causing the two or more separatepropulsion subsystems to be treatable as a single propulsion subsystemor system, for which potential under load of combined energy sources maybe used as the electric potential. Persons skilled in the art, uponreviewing the entirety of this disclosure, will be aware of variouscombinations of energy sources that may each provide power to single ormultiple propulsors in various configurations.

With continued reference to FIG. 1 , aircraft 100 may include a flightcomponent 108 that includes at least a nacelle 108. For the purposes ofthis disclosure, a “nacelle” is a streamlined body housing, which issized according to that which is houses, such as without limitation anengine, a fuel store, or a flight component. When attached by a pylonentirely outside an airframe 104 a nacelle may sometimes be referred toas a pod, in which case an engine within the nacelle may be referred toas a podded engine. In some cases an aircraft cockpit may also be housedin a nacelle, rather than in a conventional fuselage. At least a nacellemay substantially encapsulate a propulsor, which may include a motor oran engine. At least a nacelle may be mechanically connected to at leasta portion of aircraft 100 partially or wholly enveloped by an outer moldline of the aircraft 100. At least a nacelle may be designed to bestreamlined. At least a nacelle may be asymmetrical about a planecomprising the longitudinal axis of the engine and the yaw axis ofmodular aircraft 100.

With continued reference to FIG. 1 , a flight component may include apropulsor. A “propulsor,” as used herein, is a component or device usedto propel a craft by exerting force on a fluid medium, which may includea gaseous medium such as air or a liquid medium such as water. For thepurposes of this disclosure, “substantially encapsulate” is the state ofa first body (e.g., housing) surrounding all or most of a second body. Amotor may include without limitation, any electric motor, where anelectric motor is a device that converts electrical energy intomechanical work for instance by causing a shaft to rotate. A motor maybe driven by direct current (DC) electric power; for instance, a motormay include a brushed DC motor or the like. A motor may be driven byelectric power having varying or reversing voltage levels, such asalternating current (AC) power as produced by an alternating currentgenerator and/or inverter, or otherwise varying power, such as producedby a switching power source. A motor may include, without limitation, abrushless DC electric motor, a permanent magnet synchronous motor, aswitched reluctance motor, and/or an induction motor; persons skilled inthe art, upon reviewing the entirety of this disclosure, will be awareof various alternative or additional forms and/or configurations that amotor may take or exemplify as consistent with this disclosure. Inaddition to inverter and/or switching power source, a circuit drivingmotor may include electronic speed controllers or other components forregulating motor speed, rotation direction, torque, and/or dynamicbraking. Motor may include or be connected to one or more sensorsdetecting one or more conditions of motor; one or more conditions mayinclude, without limitation, voltage levels, electromotive force,current levels, temperature, current speed of rotation, positionsensors, and the like. For instance, and without limitation, one or moresensors may be used to detect back-EMF, or to detect parameters used todetermine back-EMF, as described in further detail below. One or moresensors may include a plurality of current sensors, voltage sensors, andspeed or position feedback sensors. One or more sensors may communicatea current status of motor to a flight controller and/or a computingdevice; computing device may include any computing device as describedin this disclosure, including without limitation, a flight controller.

With continued reference to FIG. 1 , a motor may be connected to athrust element. Thrust element may include any device or component thatconverts mechanical work, for example of a motor or engine, into thrustin a fluid medium. Thrust element may include, without limitation, adevice using moving or rotating foils, including without limitation oneor more rotors, an airscrew or propeller, a set of airscrews orpropellers such as contra-rotating propellers or co-rotating propellers,a moving or flapping wing, or the like. Thrust element may includewithout limitation a marine propeller or screw, an impeller, a turbine,a pump-jet, a paddle or paddle-based device, or the like. Thrust elementmay include a rotor. Persons skilled in the art, upon reviewing theentirety of this disclosure, will be aware of various devices that maybe used as thrust element. A thrust element may include any device orcomponent that converts mechanical energy (i.e., work) of a motor, forinstance in form of rotational motion of a shaft, into thrust within afluid medium. As another non-limiting example, a thrust element mayinclude an eight-bladed pusher propeller, such as an eight-bladedpropeller mounted behind the engine to ensure the drive shaft is incompression.

With continued reference to FIG. 1 , in nonlimiting embodiments, atleast a flight component 108 may include an airbreathing engine such asa jet engine, turbojet engine, turboshaft engine, ramjet engine,scramjet engine, hybrid propulsion system, turbofan engine, or the like.At least a flight component 108 may be fueled by any fuel described inthis disclosure, for instance without limitation Jet-A, Jet-B, dieselfuel, gasoline, or the like. In nonlimiting embodiments, a jet engine isa type of reaction engine discharging a fast-moving jet that generatesthrust by jet propulsion. While this broad definition can includerocket, water jet, and hybrid propulsion, the term jet engine, in somecases, refers to an internal combustion airbreathing jet engine such asa turbojet, turbofan, ramjet, or pulse jet. In general, jet engines areinternal combustion engines. As used in this disclosure, a “combustionengine” is a mechanical device that is configured to convert mechanicalwork from heat produced by combustion of a fuel. In some cases, acombustion engine may operate according to an approximation of athermodynamic cycle, such as without limitation a Carnot cycle, a Chengcycle, a Combined cycle, a Brayton cycle, an Otto cycle, an Allam powercycle, a Kalina cycle, a Rankine cycle, and/or the like. In some cases,a combustion engine may include an internal combustion engine. Aninternal combustion engine may includes heat engine in which combustionof fuel occurs with an oxidizer (usually air) in a combustion chamberthat comprises a part of a working fluid flow circuit. Exemplaryinternal combustion engines may without limitation a reciprocatingengine (e.g., 4-stroke engine), a combustion turbine engine (e.g., jetengines, gas turbines, Brayton cycle engines, and the like), a rotaryengine (e.g., Wankel engines), and the like. In nonlimiting embodiments,airbreathing jet engines feature a rotating air compressor powered by aturbine, with leftover power providing thrust through a propellingnozzle—this process may be known as a Brayton thermodynamic cycle. Jetaircraft may use such engines for long-distance travel. Early jetaircraft used turbojet engines that were relatively inefficient forsubsonic flight. Most modern subsonic jet aircraft use more complexhigh-bypass turbofan engines. In some cases, they give higher speed andgreater fuel efficiency than piston and propeller aeroengines over longdistances. A few air-breathing engines made for highspeed applications(ramjets and scramjets) may use a ram effect of aircraft's speed insteadof a mechanical compressor. An airbreathing jet engine (or ducted jetengine) may emit a jet of hot exhaust gases formed from air that isforced into the engine by several stages of centrifugal, axial or ramcompression, which is then heated and expanded through a nozzle. In somecases, a majority of mass flow through an airbreathing jet engine may beprovided by air taken from outside of the engine and heated internally,using energy stored in the form of fuel. In some cases, a jet engine mayinclude are turbofans. Alternatively and/or additionally, jet engine mayinclude a turbojets. In some cases, a turbofan may use a gas turbineengine core with high overall pressure ratio (e.g., 40:1) and highturbine entry temperature (e.g., about 1800 K) and provide thrust with aturbine-powered fan stage. In some cases, thrust may also be at leastpartially provided by way of pure exhaust thrust (as in a turbojetengine). In some cases, a turbofan may have a high efficiency, relativeto a turbojet. In some cases, a jet engine may use simple ram effect(e.g., ramjet) or pulse combustion (e.g., pulsejet) to give compression.Persons skilled in the art, upon reviewing the entirety of thisdisclosure, will be aware of various devices that may be used as athrust element.

With continued reference to FIG. 1 , an aircraft 100 may include aflight controller. As used in this disclosure, a “flight controller” isa device that generates signals for controlling at least a flightcomponent 108 of an aircraft 100. In some cases, a flight controllerincludes electronic circuitry, such as without limitation a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), and/or a computing device. Flight controller may use sensorfeedback to calculate performance parameters of motor, including withoutlimitation a torque versus speed operation envelope. Persons skilled inthe art, upon reviewing the entirety of this disclosure, will be awareof various devices and/or components that may be used as or included ina motor or a circuit operating a motor, as used and described in thisdisclosure.

With continued reference to FIG. 1 , computing device may include anycomputing device as described in this disclosure, including withoutlimitation a microcontroller, microprocessor, digital signal processor(DSP) and/or system on a chip (SoC) as described in this disclosure.Computing device may include, be included in, and/or communicate with amobile device such as a mobile telephone or smartphone. Computing devicemay include a single computing device operating independently, or mayinclude two or more computing device operating in concert, in parallel,sequentially or the like; two or more computing devices may be includedtogether in a single computing device or in two or more computingdevices. Computing device may interface or communicate with one or moreadditional devices as described below in further detail via a networkinterface device. Network interface device may be utilized forconnecting computing device to one or more of a variety of networks, andone or more devices. Examples of a network interface device include, butare not limited to, a network interface card (e.g., a mobile networkinterface card, a LAN card), a modem, and any combination thereof.Examples of a network include, but are not limited to, a wide areanetwork (e.g., the Internet, an enterprise network), a local areanetwork (e.g., a network associated with an office, a building, a campusor other relatively small geographic space), a telephone network, a datanetwork associated with a telephone/voice provider (e.g., a mobilecommunications provider data and/or voice network), a direct connectionbetween two computing devices, and any combinations thereof. A networkmay employ a wired and/or a wireless mode of communication. In general,any network topology may be used. Information (e.g., data, softwareetc.) may be communicated to and/or from a computer and/or a computingdevice. Computing device may include but is not limited to, for example,a computing device or cluster of computing devices in a first locationand a second computing device or cluster of computing devices in asecond location. Computing device may include one or more computingdevices dedicated to data storage, security, distribution of traffic forload balancing, and the like. Computing device may distribute one ormore computing tasks as described below across a plurality of computingdevices of computing device, which may operate in parallel, in series,redundantly, or in any other manner used for distribution of tasks ormemory between computing devices. Computing device may be implementedusing a “shared nothing” architecture in which data is cached at theworker, in an embodiment, this may enable scalability of aircraft 100and/or computing device.

With continued reference to FIG. 1 , computing device may be designedand/or configured to perform any method, method step, or sequence ofmethod steps in any embodiment described in this disclosure, in anyorder and with any degree of repetition. For instance, computing devicemay be configured to perform a single step or sequence repeatedly untila desired or commanded outcome is achieved; repetition of a step or asequence of steps may be performed iteratively and/or recursively usingoutputs of previous repetitions as inputs to subsequent repetitions,aggregating inputs and/or outputs of repetitions to produce an aggregateresult, reduction or decrement of one or more variables such as globalvariables, and/or division of a larger processing task into a set ofiteratively addressed smaller processing tasks. Computing device mayperform any step or sequence of steps as described in this disclosure inparallel, such as simultaneously and/or substantially simultaneouslyperforming a step two or more times using two or more parallel threads,processor cores, or the like; division of tasks between parallel threadsand/or processes may be performed according to any protocol suitable fordivision of tasks between iterations. Persons skilled in the art, uponreviewing the entirety of this disclosure, will be aware of various waysin which steps, sequences of steps, processing tasks, and/or data may besubdivided, shared, or otherwise dealt with using iteration, recursion,and/or parallel processing.

Still referring to FIG. 1 , a propulsor of aircraft 100 may comprise acombustion engine. Combustion engine is configured to burn the fuel fromthe fuel source to produce mechanical work. Resulting mechanical workmay be used to power the propulsor. In some cases, a combustion enginemay operate according to an approximation of a thermodynamic cycle, suchas without limitation a Carnot cycle, a Cheng cycle, a Combined cycle, aBrayton cycle, an Otto cycle, an Allam power cycle, a Kalina cycle, aRankine cycle, and/or the like. In some cases, a combustion engine mayinclude an internal combustion engine. An internal combustion engine mayinclude heat engine in which combustion of fuel occurs with an oxidizer(usually air) in a combustion chamber that includes a part of a workingfluid flow circuit. Exemplary internal combustion engines may withoutlimitation a reciprocating engine (e.g., 4-stroke engine), a combustionturbine engine (e.g., jet engines, gas turbines, Brayton cycle engines,and the like), a rotary engine (e.g., Wankel engines), and the like. Innonlimiting embodiments, airbreathing jet engines feature a rotating aircompressor powered by a turbine, with leftover power providing thrustthrough a propelling nozzle—this process may be known as a Braytonthermodynamic cycle. Jet aircraft may use such engines for long-distancetravel. Early jet aircraft used turbojet engines that were relativelyinefficient for subsonic flight. Most modern subsonic jet aircraft usemore complex high-bypass turbofan engines. In some cases, they givehigher speed and greater fuel efficiency than piston and propelleraeroengines over long distances. A few air-breathing engines made forhighspeed applications (ramjets and scramjets) may use a ram effect ofaircraft's speed instead of a mechanical compressor. An airbreathing jetengine (or ducted jet engine) may emit a jet of hot exhaust gases formedfrom air that is forced into the engine by several stages ofcentrifugal, axial or ram compression, which is then heated and expandedthrough a nozzle. In some cases, a majority of mass flow through anairbreathing jet engine may be provided by air taken from outside of theengine and heated internally, using energy stored in the form of fuel.In some cases, a jet engine may include are turbofans. Alternativelyand/or additionally, jet engine may include a turbojets. In some cases,a turbofan may use a gas turbine engine core with high overall pressureratio (e.g., 40:1) and high turbine entry temperature (e.g., about 1800K) and provide thrust with a turbine-powered fan stage. In some cases,thrust may also be at least partially provided by way of pure exhaustthrust (as in a turbojet engine). In some cases, a turbofan may have ahigh efficiency, relative to a turbojet. In some cases, a jet engine mayuse simple ram effect (e.g., ramjet) or pulse combustion (e.g.,pulsejet) to give compression. Persons skilled in the art, uponreviewing the entirety of this disclosure, will be aware of variousdevices that may be used as a thrust element. Additionally, at least anelectric motor of the propulsor may be operatively connected with a fuelcell by way of electrical communication, for example through one or moreconductors.

Still referring to FIG. 1 , aircraft 100 may comprise at least anauxiliary power unit powered by the fuel and mechanically affixed to theaircraft. As used in this disclosure, an “auxiliary power unit” is apower system, such as without limitation an electrical circuit ormechanical power source, that provides electrical energy tonon-propulsor flight components of an aircraft. Exemplary non-limitingnon-propulsor flight component include an avionic system, a flightcontrol system, an environmental control system, and anti-ice system, alighting system, a fuel system, a braking system, and/or a landing gearsystem.

Referring now to FIG. 2A, an exemplary embodiment of a fuel tank 200(also referred to as a “tank”) is shown. In this disclosure, a “fueltank” is a container of fuel, which is often flammable. In anembodiment, a fuel tank 200 stores fuel to power aircraft 100. A fueltank 200 may be permanently attached to aircraft 100. As used in thisdisclosure, a tank may be “permanently attached” when it is configuredto not be removed during ordinary use. For example, a tank permanentlyattached to aircraft may be removed during maintenance or overhaul butis otherwise a permanent flight component of the aircraft. A fuel tank200 of a plurality of fuel tanks may include one or more compartments tostore fuel in. Tank 200 may be configured to store a liquified gas fuel.As used in this disclosure, a “liquified gas fuel” is a fuel that atstandard atmospheric conditions or when utilized (e.g., combusted) isgas and is stored as a fuel. Liquified gas fuels include withoutlimitation liquid hydrogen, propane, and liquified natural gas. A fueltank 200 of a plurality of fuel tanks may be a part of fuel deliverysystem for an engine, in which the fuel may be stored inside a fuel tankand then propelled or released into an engine, such as withoutlimitation a combustion engine. Tank 200 may be a pressure vessel. A“pressure vessel” is a container configured to hold fluids at a pressurethat may differ from an ambient pressure. Pressure vessel may beconfigured to be pressurized in order to allow flow of gaseous fuel froma tank 200, for example without a need to pump. In an embodiment, butwithout limitation, a tank 200 may act as a pressure vessel to store thefuel at a high pressures above 5 psig, 15 psig, 50 psig, or the like. Atank 200 may be made of any material able to withstand such highpressure, such as but without limitation, aluminum, steel, titanium,carbon fiber, composite materials, or the like. Furthermore, a tank 200may further include an inner tank and an outer wall. As used herein, an“inner wall” is the inner barrier of a tank that is in contact with thefuel. As used herein, an “outer wall” is the outer barrier of a tankthat is in contact with an environment outside the tank. There may beinsulation between the outer and inner wall. A tank 200 may also includesafety valves, closures, vessel threads, or any other features that canbe found on fuel tanks.

Now referencing FIG. 2B, a cross sectional view 202 of fuel tank 200.Tank 200 includes an inner wall 204. Inner wall 204 may be in directcontact with the fuel in the fuel tank 200. Inner wall 204 may beconfigured to hold the fuel. Inner wall 204 may also be direct orindirect contact with an interstitial volume 208 found between the innerwall 204 and the outer wall 212. As used herein, an “interstitialvolume” is an intervening space between two barriers. Barriers mayinclude the outer and inner wall. Inner wall 204 may be made from carbonpolymer composite (carbon epoxy), aluminum, composite, or the like, or acombination thereof. In an embodiment, inner wall 204 may include analuminum liner in combination with the carbon epoxy material. Carbonepoxy may be used over aluminum as it is lighter and has a lower thermalexpansion coefficient as compared to aluminum. However, carbon epoxy mayleak more than aluminum. Thermal expansion coefficient may be animportant factor in the inner wall material as exposure tolow-temperature (e.g., −252.87° C. at 1.013 bar of pressure) liquifiedgas fuel in the fuel tank 200 causes the inner wall 204 to contract.Aluminum may substantially vary in size when exposed to the variationsin temperature of a typical liquified gas fuel tank. The coefficient ofthermal expansion (a) of aluminum is approximately 23×10⁶° C.⁻¹. Changein length (L) for a given piece of aluminum subjected to a temperatureincrease is determined by the following equation, wherein t is thetemperature increase.ΔL=αLtThe contraction of the inner wall 204 may cause pressure, such aswithout limitation ununiform pressures, on the outer wall 212 or theinterstitial volume 208.

Continuing to reference FIG. 2B, tank 200 may include a sensing systemconnected to a controller to monitor and control leakage from the tank.Sensing system is described with respect to FIG. 3 . As discussed above,inner wall 204 may leak gaseous fuel (e.g., gaseous hydrogen). Outerwall 212 may contain the leakage such that the gaseous fuel does notescape the tank 200. However, leaked gaseous fuel may need to be purgedfrom the interstitial volume 208 to maintain a gaseous fuel concertation(e.g., hydrogen concentration) below that which supports combustion. Insome cases, tank 200 may be configured to prevent hydrogen volumetricconcentration from exceeding 4% within interstitial volume. Above thisthreshold value, in some cases, the hydrogen may become combustible whenmixed with oxygen in the air. In some embodiments, a threshold forpurging hydrogen may be set lower than 4%, for instance 1%, 0.1%, or0.01% to account for a margin of safety. In an embodiment, sensingsystem may purge interstitial volume to keep hydrogen gas at or below1%, 0.1%, or 0.01% hydrogen volumetric concentration of the interstitialvolume 208. Purged gaseous fuel may be released overboard. Sensingsystem may include a gas sensor, as discussed in FIG. 1 , that maydetect gaseous fuel in the interstitial volume. Gas sensor may measuregaseous fuel concentration (e.g., hydrogen concentration) in theinterstitial volume. A gas sensor may include optical fiber surfaceplasmon resonance (SPR) sensors. As non-limiting examples, SPR sensorsmay include fiber bragg gratings coated with a palladium layer, amicromirror, or a tapered wire coated with palladium. Gas sensor mayalso include electrochemical hydrogen sensors, microelectromechanicalsystem (MEMS) hydrogen sensors, thin film sensors, thick film sensors,chemochromic hydrogen sensors, diode based Schottky sensors, or thelike. Alternatively or additionally, gas sensor may be configured tomonitor purge flow rate. “Purge flow rate”, as used in this disclosure,is the rate that of gas being vented out. Purge flow rate may bemeasured in mass flow rate, pressure (e.g., pressure difference),volumetric flow rate, gas velocity, or the like. Purge flow rate may bemonitored using a velocity sensor physically or communicativelyconnected to the gas sensor. Purge flow rate may be measured using oneor more pressure sensors. Purge flow rate may be measured using a pitottube. Purge flow rate may be monitored at a vent. Purge flow rate may beused to identify excessive gas leakage, which may help avoid suddenfailure. Sensing system may include a vent 216 attached to tank 200. Asused in this disclosure, a “vent” is an opening and/or apertureconfigured to allow one or more fluids to pass. Gas sensor may becommunicatively connected to a controller that may control a vent 216 toventilate the interstitial volume 208 of gaseous discharge. In anembodiment, controller may signal the vent to switch from a closedposition to an open position when a threshold gas concentration value isdetected. Threshold gas concentration value may be 1%, 0.1%, or 0.01%hydrogen volumetric concentration of the interstitial volume 208. Insome embodiments, threshold gas concentration may be 3%, or 5% andgreater. In some cases, vent 216 may include a check valve. A checkvalve may be used to prevent backflow of gases. As used in thisdisclosure, a “check valve” is a valve that permits flow of a fluid onlyin certain (e.g., one) directions. In some cases, check valve may beconfigured to allow flow of fluids substantially only away from tank 200while preventing back flow of vented fluid to tank 200. Vent may alsoinclude a pressure regulator. A “pressure regulator” is a type of valvethat controls the pressure of a fluid. Venting gaseous fuel from tank200 prevents over-pressurizing or other events that may causecatastrophic damage or harm. It may also desirable, when aircraft 100 isgrounded, to connect a system of lines and tanks to the vent to collectthe boiled-off fuel. In some cases, the collected gaseous fuel can becompressed by a pump into storage tanks and then cooled to liquidtemperatures for reuse as aircraft fuel. In some cases, vent 216 may beconfigured to prevent condensation resulting from venting of gas. Forinstance and without limitation, vent 216 may include insulation,cascading pressure vessels, gradual throttling valves, clean dry airmixing, and the like to prevent one or more of gas expansion,temperature drop, and/or condensation.

Continuing to reference FIG. 2B, tank 200 may include a gap 220. Gap 220may be in the interstitial volume 208. As used herein, “gap” refers tothe portion of the interstitial volume that is not taken up by astructure, such as insulation. In some cases, gap 220 may be configuredto resist conductive and/or convective heat transfer, for instancebetween inner and outer walls of tank 200. The gap may be ventilated. Inan embodiment, gap may be connected to the vent 216 such that the ventmay ventilate fuel gas out of the gap 220. The gap may allow the gaseousfuel that leaks from the inner wall 204 to be purged from the tank 200.Gap may be located between the outside face of the inner wall 204 andinsulation. In some cases, vented gas from the gap 220 may be ventedoverboard outside of aircraft. Alternatively or additionally, in somecases, vented gases from the gap 220 may be vented into cabin (and thenvented using cabin ventilation systems). In some cases, purge gas may bepumped into gap 220. Purge gas may include air, nitrogen, recirculatedgas, or the like. In some cases, purge gas may be filtered and/or driedprior to pumping into gap 220, for example to prevent condensationand/or contamination of an inner or outer tank wall which could lead todecreased insulation.

Continuing to reference FIG. 2B, tank 200 includes at least a reflectivefilm layer and at least a structural insulation layer. At least areflective film layer and at least a structural insulation layer mayform insulation for the tank 200. As used herein, “reflective film” is athin layer of reflective material that lowers heat transfer. Reflectivefilm layer may be a coating, for instance on a surface of inner and/orouter wall of a tank. Reflective film layer may include, withoutlimitation, gold, nickel, silver, or the like. Reflective film layer maybe a coating on the inner or outer wall. Reflective film layer mayinclude a high polish surface on one or more of inner or outer walls. Ahigh polish surface may have a Ra value less than 10 microns, less than1 micron, or less than 0.5 microns. In some cases, reflective film layermay be configured to limit radiative heat transfer, for example frominner wall to outer wall. Interstitial volume 208 may include severallayers of reflective film 228 and structural insulation 232. Reflectivefilm 228 may be sandwiched in between layers of structural insulation232 as shown in FIG. 2 . In an embodiment, there may be 5 layers ofinsulation, wherein a “layer of insulation” is defined as a combinationof one layer of reflective film and one layer of structural insulation.The number of layers of insulation may be determined by the thermalresistance requirement of the interstitial volume 208. Thermalresistance is a property of the material's thermal conductivity,thickness, and area.

Continuing to reference FIG. 2B, at least a reflective film layer may beused in the insulation. Reflective film 228 may include a metal sheet,for example a sheet of an aluminum alloy, silver, gold, titanium,stainless steel, or the like. Reflective film 228 may include ametalized plastic film. Plastic film may include Mylar, Kapton, orTedlar. Reflective film 228 may use nickel, aluminum, gold, silver, acombination thereof, or other metals. Reflective film 228 may usepolyimide or polyester, or the like. Reflective film 228 may reduce heattransfer from radiation due to the reflective nature. Reflective film228 may be a multi-layer insulation (MLI). Persons skilled in the art,upon reviewing the entirety of this disclosure, will be aware of variousmaterials used in reflective films. Reflective film 228 may be used incombination with a structural insulation 232 to decrease heat transferbetween the inner wall 204 and the outer wall 208. Insulation may beused to prevent air or water from freezing on the outer surface of theinner wall 204.

Still referencing FIG. 2B, insulation may also include at least astructural insulation layer. There may be a plurality of structuralinsulation layers, wherein the reflective film 228 is in between eachlayer of structural insulation 232. “Structural insulation,” as usedherein, is a form of self-supporting insulation within the interstitialvolume. In some cases, structural insulation may support otherinsulation layers (e.g., reflective film layer) within the interstitialvolume. Structural insulation 232 may, in some cases, support the outerwall 212 against the vacuum in the interstitial volume 208, for exampleby providing compressive forces between inner and outer walls. Vacuummay be used to evacuate volume between the inner wall 204 and the outerwall 212. Vacuum may also be result of a pressure differential (i.e.,higher pressure outside of outer wall than in interstitial volume).Additionally, structural insulation 232 may support the inner wall 204against the high pressure from the liquified gas fuel. Structuralinsulation 232 may be divided into blocks such that the structuralinsulation 232 is discontinuous. Gaps between the structural insulation232 may provide gaps to allow evacuation and leak detection. Gapsbetween structural insulation 232 may provide fluidic pathways forgaseous discharge. Structural insulation 232 may be composed from aporous or non-porous insulation. Structural insulation 232 may becomposed of, as non-limiting examples, Aerogel, vermiculite, fiberglass,X-Aerogel, crosslinked Aerogel, firebrick, or any other insulation witha low thermal conductivity coefficient. A low thermal conductivity maybe any thermal conductivity less than 0.10, 0.01, or 0.001 W/m-k.Structural insulation 232 may limit heat transfer by conduction.

Still referencing FIG. 2B, tank 200 includes an outer wall 212. Outerwall 212 may be in between an outside environment (e.g., aircraft cabinenvironment) and interstitial volume 208. Outer wall 212 may be offsetfrom the inner wall 204 such that the interstitial volume 208 is inbetween. Outer wall 212 may provide damage protection from externalelements such as temperature, transportation, or the like that may occurwithin the aircraft. Tank 200 may be stored within the aircraft 100. Insome embodiments, tank 200 may be stored within the outer mold line(skin) of the aircraft body (such as blended wing body 104).Alternatively, tank 200 may be mounted outside the aircraft within anacelle. Outer wall 212 may prevent permeation of gases originating fromwithin inner wall 204 and/or interstitial volume 208. Outer wall 212 maybe composed of one or more of steel and aluminum to prevent thepermeation of gases from the inner wall 204 of the tank 200. Outer wall212 may also be composed of other material, such as composites, carbonpolymer composites, titanium, and the like. Outer wall 212 may becomposed of materials that are able to withstand the compression loadsfrom a pressure differential between in the interstitial volume 208 andan environment outside the outer wall. In an embodiment, outer wall 212may be subjected to compression loads because the outer wall 212 mayshrink due to the vacuum in the interstitial volume. In someembodiments, outer wall 212 may be corrugated so that the outer wall 212may accept changes in its diameter with flexure. In an embodiment,corrugated outer wall 212 may minimize thickness of the outer wall 212because a corrugated outer wall may be stronger against compressionloads than a non-corrugated outer wall, therefore less material isneeded for a corrugated outer wall. In some embodiments, outer wall 212may include a corrugated piece of material sandwiched between twonon-corrugated pieces of material. The non-corrugated pieces of materialmay provide additional strength and insulation to the outer wall 212 andincrease the durability of it.

Blended wing aircrafts may be consistent with any blended wing aircraftand fuel tank as disclosed in U.S. patent application Ser. No.17/731,622 entitled “BLENDED WING BODY AIRCRAFT WITH A COMBUSTION ENGINEAND METHOD OF USE” and filed on Apr. 28, 2022. Permanent tanks may beconsistent with any permanent tank as disclosed U.S. patent applicationSer. No. 17/731,655 entitled “SYSTEMS AND METHODS FOR A BLENDED WINGBODY AIRCRAFT WITH PERMANENT TANKS” and filed on Apr. 28, 2022. Fueltanks may be consistent with any fuel tank as disclosed in U.S. patentapplication Ser. No. 17/731,728 entitled “AN AIRCRAFT WITH FUEL TANKSSTORED AFT OF A CABIN IN A MAIN BODY AND A METHOD FOR MANUFACTURING” andfiled on Apr. 28, 2022. Aircraft may use fuel cells consistent with anyfuel cells as disclosed in U.S. patent application Ser. No. 17,478/724entitled “BLENDED WING BODY AIRCRAFT WITH A FUEL CELL AND METHOD OF USE”and filed on Sep. 17, 2021.

Now referring to FIG. 3 , a block diagram of a sensing system 300 foraircraft 100. Sensing system may include a controller 304. Controller304 may include any computing device as described in this disclosure,including without limitation a microcontroller, microprocessor, digitalsignal processor (DSP) and/or system on a chip (SoC) as described inthis disclosure. Computing device may include, be included in, and/orcommunicate with a mobile device such as a mobile telephone orsmartphone. Controller 304 may include a single computing deviceoperating independently, or may include two or more computing deviceoperating in concert, in parallel, sequentially or the like; two or morecomputing devices may be included together in a single computing deviceor in two or more computing devices. Controller 304 may interface orcommunicate with one or more additional devices as described below infurther detail via a network interface device. Network interface devicemay be utilized for connecting controller 304 to one or more of avariety of networks, and one or more devices. Examples of a networkinterface device include, but are not limited to, a network interfacecard (e.g., a mobile network interface card, a LAN card), a modem, andany combination thereof. Examples of a network include, but are notlimited to, a wide area network (e.g., the Internet, an enterprisenetwork), a local area network (e.g., a network associated with anoffice, a building, a campus or other relatively small geographicspace), a telephone network, a data network associated with atelephone/voice provider (e.g., a mobile communications provider dataand/or voice network), a direct connection between two computingdevices, and any combinations thereof. A network may employ a wiredand/or a wireless mode of communication. In general, any networktopology may be used. Information (e.g., data, software etc.) may becommunicated to and/or from a computer and/or a computing device.Controller 304 may include but is not limited to, for example, acomputing device or cluster of computing devices in a first location anda second computing device or cluster of computing devices in a secondlocation. controller 304 may include one or more computing devicesdedicated to data storage, security, distribution of traffic for loadbalancing, and the like. controller 304 may distribute one or morecomputing tasks as described below across a plurality of computingdevices of computing device, which may operate in parallel, in series,redundantly, or in any other manner used for distribution of tasks ormemory between computing devices. controller 304 may be implementedusing a “shared nothing” architecture in which data is cached at theworker, in an embodiment, this may enable scalability of aircraft 100and/or computing device.

With continued reference to FIG. 3 , controller 304 may be designedand/or configured to perform any method, method step, or sequence ofmethod steps in any embodiment described in this disclosure, in anyorder and with any degree of repetition. For instance, controller 304may be configured to perform a single step or sequence repeatedly untila desired or commanded outcome is achieved; repetition of a step or asequence of steps may be performed iteratively and/or recursively usingoutputs of previous repetitions as inputs to subsequent repetitions,aggregating inputs and/or outputs of repetitions to produce an aggregateresult, reduction or decrement of one or more variables such as globalvariables, and/or division of a larger processing task into a set ofiteratively addressed smaller processing tasks. Controller 304 mayperform any step or sequence of steps as described in this disclosure inparallel, such as simultaneously and/or substantially simultaneouslyperforming a step two or more times using two or more parallel threads,processor cores, or the like; division of tasks between parallel threadsand/or processes may be performed according to any protocol suitable fordivision of tasks between iterations. Persons skilled in the art, uponreviewing the entirety of this disclosure, will be aware of various waysin which steps, sequences of steps, processing tasks, and/or data may besubdivided, shared, or otherwise dealt with using iteration, recursion,and/or parallel processing.

Continuing to reference FIG. 3 , controller 304 may be connected to agas sensor 308. Gas sensor 308 and controller 304 may be communicativelyconnected. Gas sensor 308 may be consistent with any gas sensordisclosed as part of this disclosure. Controller may be consistent withany controller disclosed as part of this disclosure. Gas sensor 308 maydetect gas concentrations such as gaseous fuel concentrations. Gassensor may monitor purge flow rate by monitoring the velocity of gasleaving vent 312. Velocity, mass flow rate, or the like may be measuredusing a pressure sensor or velocity sensor communicatively connected orphysically connected to the gas sensor 308. Vent may be consistent withany vent as discussed above, Gas sensor 308 may be consistent with anygas sensor as described above. Gas sensor 308 may cause the controller304 to issue signals to a vent 312, such as a purge valve or pump. Forexample, the signals may cause the vent 312 to open if the gaseous fuelconcentration exceeds a threshold value, such as the threshold valuesdiscussed above. In another example, gas sensor 308 may send a signalthat causes the vent 312 to open if the gas sensor 308 detects excessivegas leakage, which may help avoid sudden failure of the tank.

Continuing with reference to FIG. 3 , in some embodiments controller 304may control gaseous fuel (i.e., fuel vapor) concentration. For example,in some cases, gaseous fuel concentration within an interstitial volume(i.e., gap 220) between an inner wall and an outer wall may becontrolled. In some embodiments, gaseous fuel concentration may beadjusted by controlled admission of air or other gases into gap 220. Insome cases, admission of air or other gases may be controlled by vent308. Vent 308 may be configured to allow of admission of air or othergases (e.g., nitrogen) in to gap 220. In some cases, air may come fromwithin aircraft cabin and/or from outside of aircraft. In some cases,other gases may help prevent combustion of gaseous fuel. For instance,if interstitial volume 220 is filled with a mixture of nitrogen and fuelvapor, combustion is not possible due to absence of oxygen. In somecases, using administrating an inert gas into interstitial volume 220may be favorable because greater concentrations of fuel vapor may bepermitted. In some cases, nitrogen may be supplied by an onboard inertgas generator system. In some cases, an onboard inert gas generatorsystem may be in place to reduce flammability of fuel vapor, generally.In some embodiments, gas admission rate may be controlled in concertwith interstitial volume pressure to result in a combination of desiredpressure and fuel vapor concentration. For instance in some embodiments,controller 304 may control pressure within the interstitial volume 220.Generally lower gas pressure within interstitial volume 220 willincrease thermal insulation. In some cases, interstitial volume pressuremay be controller by way of pump rate (e.g., vacuum pump rate).

Now referring to FIG. 4 , a method of manufacturing 400 for amulti-walled fuel tank for an aircraft 100 is shown. Step 405 of method400 includes receiving a blended wing body. Blended wing body may beconsistent with any blended wing body as discussed herein and inreference to FIG. 1 . Step 410 of method 400 includes manufacturing atleast a fuel tank configured to store liquified gas fuel. Fuel tank maycontain liquified gas fuel. Manufacturing a fuel tank includes receivingan inner wall. Inner wall may include an aluminum liner to help preventthe permeation of gases. Inner wall may be consistent with any innerwall as discussed herein and with reference to FIG. 2B. Manufacturing afuel tank also includes receiving an outer wall. Outer wall may beoffset from the inner wall. The offset space may include an interstitialvolume. Outer wall may be corrugated to increase the strength of thewall and decrease the thickness of the wall. Outer wall may beconfigured to change sizes due to the evacuation of the interstitialvolume. The vacuum may put compression loads on the outer wall causingthe outer wall to shrink. Outer wall may be consistent with any outerwall as discussed herein, and with reference to FIG. 2 .

Continuing to reference FIG. 4 , manufacturing a fuel tank also includesforming an interstitial volume including at least a reflective filmlayer and at least a structural insulation layer between the inner walland the outer wall. Interstitial volume may include a gap to allowleaked gases to be purged. Gap may be found between the blocks ofstructural insulation as shown in FIG. 2B. Insulation may include layersof reflective film sandwiched in between structural insulation that isdivided into blocks. Reflective film layer may include a metalizedplastic film. In an embodiment, the metal in the reflective film layermay include aluminum, copper, or the like. Structural insulation mayinclude aerogel. Interstitial volume may be evacuated to form a vacuum.Interstitial volume may be evacuated to an absolute pressure of 0 to 5PSI. In an embodiment, interstitial volume may be evacuated through theuse of a vacuum pump. Vacuum pump may be connected to the interstitialvolume through a vent such as a valve. Structural insulation, gap,metalized plastic film, and interstitial volume may be consistent withany structural insulation, gap, metalized plastic film, and interstitialvolume, respectively, as disclosed herein.

Step 415 of method 400 includes attaching the at least a fuel tank tothe blended wing body. Fuel tank and blended wing body may beconstructed separately, then fuel tank may be independently mountedwithin. “Independently mounted,” as used herein, means mountedseparately from the structure of the aircraft or other elements withinthe aircraft. Plurality of fuel tanks may be integrated within astructure of the blended wing body. For example, fuel tanks may bemounted such that the fuel tanks may support the airframe of theaircraft. This may entail mechanically connecting the fuel tanks to theairframe. This integration of the fuel tanks makes the fuel tankspermanently attached as removing the fuel tanks may damage the airframeof the aircraft. Integration within the structure may make the fueltanks and the aircraft mutually dependent. Fuel tanks may be mountedwith rigid mounts, or linked mounts, or the like.

It is to be noted that any one or more of the aspects and embodimentsdescribed herein may be conveniently implemented using one or moremachines (e.g., one or more computing devices that are utilized as auser computing device for an electronic document, one or more serverdevices, such as a document server, etc.) programmed according to theteachings of the present specification, as will be apparent to those ofordinary skill in the computer art. Appropriate software coding canreadily be prepared by skilled programmers based on the teachings of thepresent disclosure, as will be apparent to those of ordinary skill inthe software art. Aspects and implementations discussed above employingsoftware and/or software modules may also include appropriate hardwarefor assisting in the implementation of the machine executableinstructions of the software and/or software module.

Such software may be a computer program product that employs amachine-readable storage medium. A machine-readable storage medium maybe any medium that is capable of storing and/or encoding a sequence ofinstructions for execution by a machine (e.g., a computing device) andthat causes the machine to perform any one of the methodologies and/orembodiments described herein. Examples of a machine-readable storagemedium include, but are not limited to, a magnetic disk, an optical disc(e.g., CD, CD-R, DVD, DVD-R, etc.), a magneto-optical disk, a read-onlymemory “ROM” device, a random access memory “RAM” device, a magneticcard, an optical card, a solid-state memory device, an EPROM, an EEPROM,and any combinations thereof. A machine-readable medium, as used herein,is intended to include a single medium as well as a collection ofphysically separate media, such as, for example, a collection of compactdiscs or one or more hard disk drives in combination with a computermemory. As used herein, a machine-readable storage medium does notinclude transitory forms of signal transmission.

Such software may also include information (e.g., data) carried as adata signal on a data carrier, such as a carrier wave. For example,machine-executable information may be included as a data-carrying signalembodied in a data carrier in which the signal encodes a sequence ofinstruction, or portion thereof, for execution by a machine (e.g., acomputing device) and any related information (e.g., data structures anddata) that causes the machine to perform any one of the methodologiesand/or embodiments described herein.

Examples of a computing device include, but are not limited to, anelectronic book reading device, a computer workstation, a terminalcomputer, a server computer, a handheld device (e.g., a tablet computer,a smartphone, etc.), a web appliance, a network router, a networkswitch, a network bridge, any machine capable of executing a sequence ofinstructions that specify an action to be taken by that machine, and anycombinations thereof. In one example, a computing device may includeand/or be included in a kiosk.

FIG. 5 shows a diagrammatic representation of one embodiment of acomputing device in the exemplary form of a computer system 500 withinwhich a set of instructions for causing a control system to perform anyone or more of the aspects and/or methodologies of the presentdisclosure may be executed. It is also contemplated that multiplecomputing devices may be utilized to implement a specially configuredset of instructions for causing one or more of the devices to performany one or more of the aspects and/or methodologies of the presentdisclosure. Computer system 500 includes a processor 504 and a memory508 that communicate with each other, and with other components, via abus 512. Bus 512 may include any of several types of bus structuresincluding, but not limited to, a memory bus, a memory controller, aperipheral bus, a local bus, and any combinations thereof, using any ofa variety of bus architectures.

Processor 504 may include any suitable processor, such as withoutlimitation a processor incorporating logical circuitry for performingarithmetic and logical operations, such as an arithmetic and logic unit(ALU), which may be regulated with a state machine and directed byoperational inputs from memory and/or sensors; processor 504 may beorganized according to Von Neumann and/or Harvard architecture as anon-limiting example. Processor 504 may include, incorporate, and/or beincorporated in, without limitation, a microcontroller, microprocessor,digital signal processor (DSP), Field Programmable Gate Array (FPGA),Complex Programmable Logic Device (CPLD), Graphical Processing Unit(GPU), general purpose GPU, Tensor Processing Unit (TPU), analog ormixed signal processor, Trusted Platform Module (TPM), a floating pointunit (FPU), and/or system on a chip (SoC).

Memory 508 may include various components (e.g., machine-readable media)including, but not limited to, a random-access memory component, a readonly component, and any combinations thereof. In one example, a basicinput/output system 516 (BIOS), including basic routines that help totransfer information between elements within computer system 500, suchas during start-up, may be stored in memory 508. Memory 508 may alsoinclude (e.g., stored on one or more machine-readable media)instructions (e.g., software) 520 embodying any one or more of theaspects and/or methodologies of the present disclosure. In anotherexample, memory 508 may further include any number of program modulesincluding, but not limited to, an operating system, one or moreapplication programs, other program modules, program data, and anycombinations thereof.

Computer system 500 may also include a storage device 524. Examples of astorage device (e.g., storage device 524) include, but are not limitedto, a hard disk drive, a magnetic disk drive, an optical disc drive incombination with an optical medium, a solid-state memory device, and anycombinations thereof. Storage device 524 may be connected to bus 512 byan appropriate interface (not shown). Example interfaces include, butare not limited to, SCSI, advanced technology attachment (ATA), serialATA, universal serial bus (USB), IEEE 1394 (FIREWIRE), and anycombinations thereof. In one example, storage device 524 (or one or morecomponents thereof) may be removably interfaced with computer system 500(e.g., via an external port connector (not shown)). Particularly,storage device 524 and an associated machine-readable medium 528 mayprovide nonvolatile and/or volatile storage of machine-readableinstructions, data structures, program modules, and/or other data forcomputer system 500. In one example, software 520 may reside, completelyor partially, within machine-readable medium 528. In another example,software 520 may reside, completely or partially, within processor 504.

Computer system 500 may also include an input device 532. In oneexample, a user of computer system 500 may enter commands and/or otherinformation into computer system 500 via input device 532. Examples ofan input device 532 include, but are not limited to, an alpha-numericinput device (e.g., a keyboard), a pointing device, a joystick, agamepad, an audio input device (e.g., a microphone, a voice responsesystem, etc.), a cursor control device (e.g., a mouse), a touchpad, anoptical scanner, a video capture device (e.g., a still camera, a videocamera), a touchscreen, and any combinations thereof. Input device 532may be interfaced to bus 512 via any of a variety of interfaces (notshown) including, but not limited to, a serial interface, a parallelinterface, a game port, a USB interface, a FIREWIRE interface, a directinterface to bus 512, and any combinations thereof. Input device 532 mayinclude a touch screen interface that may be a part of or separate fromdisplay 536, discussed further below. Input device 532 may be utilizedas a user selection device for selecting one or more graphicalrepresentations in a graphical interface as described above.

A user may also input commands and/or other information to computersystem 500 via storage device 524 (e.g., a removable disk drive, a flashdrive, etc.) and/or network interface device 540. A network interfacedevice, such as network interface device 540, may be utilized forconnecting computer system 500 to one or more of a variety of networks,such as network 544, and one or more remote devices 548 connectedthereto. Examples of a network interface device include, but are notlimited to, a network interface card (e.g., a mobile network interfacecard, a LAN card), a modem, and any combination thereof. Examples of anetwork include, but are not limited to, a wide area network (e.g., theInternet, an enterprise network), a local area network (e.g., a networkassociated with an office, a building, a campus or other relativelysmall geographic space), a telephone network, a data network associatedwith a telephone/voice provider (e.g., a mobile communications providerdata and/or voice network), a direct connection between two computingdevices, and any combinations thereof. A network, such as network 544,may employ a wired and/or a wireless mode of communication. In general,any network topology may be used. Information (e.g., data, software 520,etc.) may be communicated to and/or from computer system 500 via networkinterface device 540.

Computer system 500 may further include a video display adapter 552 forcommunicating a displayable image to a display device, such as displaydevice 536. Examples of a display device include, but are not limitedto, a liquid crystal display (LCD), a cathode ray tube (CRT), a plasmadisplay, a light emitting diode (LED) display, and any combinationsthereof. Display adapter 552 and display device 536 may be utilized incombination with processor 504 to provide graphical representations ofaspects of the present disclosure. In addition to a display device,computer system 500 may include one or more other peripheral outputdevices including, but not limited to, an audio speaker, a printer, andany combinations thereof. Such peripheral output devices may beconnected to bus 512 via a peripheral interface 556. Examples of aperipheral interface include, but are not limited to, a serial port, aUSB connection, a FIREWIRE connection, a parallel connection, and anycombinations thereof.

The foregoing has been a detailed description of illustrativeembodiments of the invention. Various modifications and additions can bemade without departing from the spirit and scope of this invention.Features of each of the various embodiments described above may becombined with features of other described embodiments as appropriate inorder to provide a multiplicity of feature combinations in associatednew embodiments. Furthermore, while the foregoing describes a number ofseparate embodiments, what has been described herein is merelyillustrative of the application of the principles of the presentinvention. Additionally, although particular methods herein may beillustrated and/or described as being performed in a specific order, theordering is highly variable within ordinary skill to achieve methods,systems, and software according to the present disclosure. Accordingly,this description is meant to be taken only by way of example, and not tootherwise limit the scope of this invention.

Exemplary embodiments have been disclosed above and illustrated in theaccompanying drawings. It will be understood by those skilled in the artthat various changes, omissions and additions may be made to that whichis specifically disclosed herein without departing from the spirit andscope of the present invention.

What is claimed is:
 1. An aircraft with at least a multi-walled fueltank, the aircraft comprising: a blended wing body; and at least a fueltank attached to the blended wing body and configured to store liquifiedgas fuel, wherein the at least a fuel tank further comprises: an innerwall; an outer wall; an interstitial volume between the inner wall andthe outer wall comprising of at least a reflective film layer and atleast a structural insulation layer, wherein the at least a fuel tankcomprising a sensing system comprising at least a gas sensor, whereinthe at least a gas sensor is located within a gap of the interstitialvolume and wherein the at least a gas sensor is configured to monitorpurge flow rate by measuring velocity of a gas.
 2. The aircraft of claim1, wherein the inner wall comprises carbon epoxy.
 3. The aircraft ofclaim 1, wherein the outer wall comprises one or more of aluminum andsteel.
 4. The aircraft of claim 1, wherein the at least a structuralinsulation layer is divided into blocks.
 5. The aircraft of claim 1,wherein the at least a structural insulation layer includes aerogel. 6.The aircraft of claim 1, wherein the at least a reflective film layercomprises a metalized plastic film.
 7. An aircraft with at least amulti-walled fuel tank, the aircraft comprising: a blended wing body;and at least a fuel tank attached to the blended wing body andconfigured to store liquified gas fuel, wherein the at least a fuel tankfurther comprises: an inner wall; an outer wall; an interstitial volumebetween the inner wall and the outer wall comprising of at least areflective film layer and at least a structural insulation layer,wherein the at least a fuel tank comprising a sensing system comprisingat least a gas sensor, wherein the at least a gas sensor is locatedwithin a gap of the interstitial volume further comprising a ventfluidly connected to the gap and configured to vent gas from the gap andwherein the at least a gas sensor is configured to detect fuel gasconcentration and control, using the vent, venting of the gas from thegap when a threshold gas concentration value is detected.
 8. A method ofmanufacturing a multi-walled fuel tank for an aircraft, the methodcomprising: receiving a blended wing body; manufacturing at least a fueltank configured to store liquified gas fuel, wherein manufacturing theat least a fuel tank comprises: receiving an inner wall; receiving anouter wall; and forming an interstitial volume between the inner walland the outer wall comprising at least a reflective film layer and atleast a structural insulation layer between the inner wall and the outerwall, wherein the at least a fuel tank comprising a sensing systemcomprising at least a gas sensor, wherein the at least a gas sensor islocated within a gap of the interstitial volume and wherein the at leasta gas sensor is configured to monitor purge flow rate by measuringvelocity of a gas; and attaching the at least a fuel tank to the blendedwing body.
 9. The method of claim 8, wherein the at least a structuralinsulation layer is divided into blocks.
 10. The method of claim 8,wherein the interstitial volume is evacuated to an absolute pressure ofabout 0 to 5 PSI.
 11. The method of claim 8, wherein the outer wall iscorrugated.
 12. The method of claim 8, wherein the outer wall isconfigured to change sizes due to the evacuation of the interstitialvolume.
 13. The method of claim 8, wherein the inner wall comprises analuminum liner.
 14. The method of claim 8, wherein the at least astructural insulation layer includes aerogel.
 15. The method of claim 8,wherein the at least a reflective film layer comprises a metalizedplastic film.